The channel quality of an active connection in telecommunications systems is typically checked continuously in order to make it possible to take suitable measures if the quality of the connection is poor. If the determined value for the channel quality is below a predetermined target value, then, for example, the transmission power is increased in order to increase the signal-to-noise power ratio.
Bit error rate measurements may be carried out in a telecommunications system in order to determine the channel quality of a connection—which is represented by the quality index z. In this case, measurement values in the range between 0 and 1 are generally possible, by virtue of the definition of the bit error rate b as the ratio of incorrectly received bits to the total number of received bits. In practice, the results are typically in a range Ib between 0 and 0.5. In contrast to this, the quality index z is stated as an integer value. For a Bluetooth radio interface, this is in the interval Iz of [0.255].
A linear mapping rule, which changes a measurement value of the bit error rate b from the value range Ib to a quality index z from the value range Iz does not result in efficient association. If, for example, the value range Ib for a Bluetooth radio interface is subdivided into 256 identical individual intervals, which are then associated with the values z=255 to z=0, this leads in typical transmission scenarios to only a small number of z values or even only a single z value occurring in the entire value range Iz of the quality index. The possible value range Iz is thus not used efficiently, and a rule based on a quality index such as this operates inefficiently.
One further problem is to take account of the relevant bit error rate range in a worthwhile manner. This is because the entire bit error rate range is typically not of the same interest. Frequently, more accurate allocation with higher quantization to the quality index is worthwhile in the relevant bit error rate range than in less relevant ranges. The relevance of a bit error rate range is in this case governed by application-specific requirements.